1. Technical Field of the Invention
The present invention relates to novel cosmetic compositions for topical application, more particularly in a regime or regimen for the photoprotection of the skin and/or hair against ultraviolet radiation (compositions more simply referred to hereinafter as antisun compositions), and to their use in the abovementioned cosmetic regime/regimen. More specifically still, it relates to antisun compositions comprising, in a cosmetically acceptable vehicle, a combination of at least two specific screening agents, namely, on the one hand, an insoluble organic UV-screening agent with a particle size ranging from 10 nm to 5 μm and, on the other hand, a 4,4-diarylbutadiene compound.
2. Description of Background/Related/Prior Art
It is known that light radiation with wavelengths of between 280 nm and 400 nm makes possible browning of the human epidermis and that rays with wavelengths of between 280 and 320 nm, known under the name of UV-B, cause erythemas and skin burns which may be harmful to the development of natural tanning; this UV-B radiation must therefore be screened out.
It is also known that UV-A rays, with wavelengths of between 320 and 400 nm, which cause browning of the skin, are capable of bringing about a detrimental change in the latter, in particular in the case of sensitive skin or of skin continually exposed to solar radiation. UV-A rays cause in particular a loss in the elasticity of the skin and the appearance of wrinkles, resulting in premature ageing. They promote the triggering of the erythemal reaction or accentuate this reaction in some subjects and can even be the cause of phototoxic or photoallergic reactions. It is therefore desirable also to screen out UV-A radiation.
Numerous cosmetic compositions intended for the photoprotection (UV-A and/or UV-B) of the skin have been provided to date.
These antisun compositions exist fairly often in the form of an emulsion of oil-in-water type (that is to say, a cosmetically acceptable vehicle composed of a continuous aqueous dispersing phase and of a noncontinuous oily dispersed phase) which comprises, at various concentrations, one or more conventional, lipophilic and/or hydrophilic, organic screening agents capable of selectively absorbing harmful UV radiation, these screening agents (and their amounts) being selected according to the sun protection factor desired, the sun protection factor (SPF) being expressed mathematically by the ratio of the dose of UV radiation necessary to reach the erythemogenic threshold with the UV-screening agent to the dose of UV radiation necessary to reach the erythemogenic threshold without UV-screening agent.
Suntan compositions based on 4,4-diarylbutadienes which can comprise other additional screening agents, such as methylene bis-benzotriazolyl tetramethylbutylphenol, are known from EP-0-967,200, DE-197,46,654, DE-197,55-649, EP-1-008,586, DE-100,07,017, EP-1-133,980 and EP-1-133,981.